1. Field of the Invention
The present invention relates to a continuous container-supplying apparatus and more particularly to an improvement in a continuous container-supplying apparatus used in a continuous filling and packaging system in which various packaging operations such as filling with contents, sealing of the openings of containers, etc. are performed on containers (e.g., packaging bags) while the containers are continuously conveyed at a high speed.
2. Prior Art
The continuous bag-supplying apparatus shown in FIGS. 11 through 13 is described in the U.S. patent application Ser. No. 09/523,856 which is filed by the applicant of the present patent application.
The continuous bag-supplying apparatus 1 comprises a bag holding assembly conveying device 4 which has a plurality of bag holding assemblies 3 attached at equal intervals to a conveyor belt 2, and an intermittent bag-supplying device 5 which simultaneously supplies bags to a plurality of the bag holding assemblies 3 (i.e., to n number of bag holding assemblies 3), with one bag being supplied to each bag holding assembly 3. The bag holding assembly 3 is moved in one direction along an annular track that has a pair parallel sections.
The bag holding assemblies 3 are moved intermittently on one side (the bag entry side) A of the parallel sections, with each movement covering a distance that is n times the attachment spacing of the bag holding assemblies 3, and the bag holding assemblies 3 move are further continuously at a constant speed on the other side (bag exit side) B of the parallel sections.
The intermittent bag-supplying device 5 is disposed on the bag entry side A so as to supply bags in a plurality of rows (n rows) to stopped bag holding assemblies 3. On the bag exit side B, a rotary type transfer device 6 is disposed so as to successively receives bags from the continuously moving bag holding assemblies 3 and continuously transfers the bags to the rotor 7 of an apparatus used in next process.
As shown in the schematic diagram in FIG. 14, the bag holding assembly conveying device 4 is equipped with a rotational conveying mechanism 8 and a reciprocating driving mechanism 9. The rotational conveying mechanism 8 rotationally conveys a plurality of bag holding assemblies 3 (only the bags are shown in FIG. 14) disposed at equal intervals on an endless conveyor belt 2 in one direction along the annular track by means of a variable-speed driving motor M1 The reciprocating driving mechanism 9 causes the rotational conveying mechanism 8 as a whole to perform a reciprocating motion over a specified distance along the parallel sections by means of a driving motor M2 that has a variable feeding speed.
The rotational conveying speed of the bag holding assemblies determined by the driving motor M1 and the speed of the reciprocating motion of the rotational conveying mechanism 8 determined by the driving motor M2 are set at different values during the advancing motion (the motion of the bag holding assemblies in the conveying direction on the bag exit side B is taken as the advancing motion; in FIG. 14, this is the motion from the solid line to the two-dotted (imaginary) line) and the return motion (from the two-dotted (imaginary) line to the solid line). In this case, rotational conveying speed (U1) of the bag holding assemblies determined by the driving motor M1 and the speed of the advancing motion (U3) of the rotational conveying mechanism 8 determined by the driving motor M2 are synthesized (canceled out) during the advancing motion on the bag entry side A, so that the movement speed of the bag holding assemblies becomes zero. Furthermore, on the bag exit side B, the rotational conveying speed (U1 during the advancing motion, U2 during the return motion) of the bag holding assemblies determined by the driving motor M1 during the reciprocating motion and the speed of the reciprocating motion (U3 during the advancing motion, U4 during the return motion) of the rotational conveying mechanism 8 determined by the driving motor M2 are synthesized, and the speeds are set so that the movement speed of the bag holding assemblies is always constant.
With the settings as described above, on the bag entry side A, the bag holding assembly conveying device 4 receives bags W in bag holding assemblies 3 that have a movement speed of zero (i.e., that are in a stationary state) from the intermittent bag-supplying device 5 during the advancing motion of the rotational conveying mechanism 8. Also, on the bag exit side B, the bag holding assembly conveying device 4 continuously transfers bags W to the rotary type transfer device 6 at a constant speed.
In the above continuous bag-supplying apparatus 1, the driving conditions of the respective driving motors, etc., can be determined if the following conditions are set: i.e., the processing capacity (bags/minute), the number of bags (n) supplied at one time, the attachment pitch p (in meters) of the bag holding assemblies, and the time of the advancing motion of the rotational conveying mechanism 8 (=the intermittent stopping time of the bag holding assemblies on the bag entry side A) t1 (in seconds).
The equations shown below are examples of calculations that are performed when it is assumed that the change-over from the speed during the advancing motion to the speed during the return motion (or the change-over from the speed during the return motion to the speed during the advancing motion) is performed instantaneously in the respective driving motors as shown in FIG. 15.
t2=60xc3x97n/Sxe2x88x92t1 
M=(t1xc3x97Sxc3x97P/2)/60 
U1=Sxc3x97p/2 
U2=Sxc3x97p+(t1xc3x97Sxc3x97p/2)/(60xc3x97n/Sxe2x88x92t1) 
U3=Sxc3x97p/2 
U4=(t1xc3x97Sxc3x97p/2)/(60xc3x97n/Sxe2x88x92t1) 
V1=V2=pxc3x97S 
V3=0 
V4=60xc3x97nxc3x97p/(60xc3x97n/Sxe2x88x92t1) 
The respective symbols used in the above equations have the following meanings:
t2: time of the return motion of the rotational conveying mechanism (=intermittent movement time of the container holding assemblies on the bag entry side A)
M (m): distance of the return motion of the rotational conveying mechanism (=return motion distance)
U1 (m/minute): rotational conveying speed of the bag holding assemblies (during the advancing motion of the rotational conveying mechanism)
U2 (m/minute): rotational conveying speed of the bag holding assemblies (during the return motion of the rotational conveying mechanism)
U3 (m/minute): speed of the advancing motion of the rotational conveying mechanism
U4 (m/minute): speed of the return motion of the rotational conveying mechanism
V1 (m/minute): synthesized movement speed of the bag holding assemblies on the bag exit side B (during the advancing motion of the rotational conveying mechanism)
V2 (m/minute): synthesized movement speed of the bag holding assemblies on the bag exit side B (during the return motion of the rotational conveying mechanism)
V3 (m/minute): synthesized movement speed of the bag holding assemblies on the bag entry side A (during the advancing motion of the rotational conveying mechanism)
V4 (m/minute): synthesized movement speed of the bag holding assemblies on the bag entry side A (during the return motion of the rotational conveying mechanism)
Furthermore, if the distance over which the bag holding assemblies are conveyed during the return motion on the bag entry side A (i.e., the distance obtained by the synthesis of the conveying distance of the conveyance performed by the rotational conveying mechanism and the distance of the return motion of the rotational conveying mechanism) is designated as L, then, since L may be referred to as the distance advanced by the bag holding assemblies at a synthesized speed of V4 during the return motion time of (t2/60) minutes, L may be expressed as follows:
L=V4xc3x97t2/60 
If the above-described V4 and t2 are substituted into this equation, the following equation is obtained:
L=pxc3x97n 
In other words, on the bag entry side A of the rotational conveying mechanism 8, n bag holding assemblies are conveyed at one time during the return motion time, and n bags W are supplied at one time during the advancing motion time. Accordingly, bags W can be intermittently and successively supplied to all the bag holding assemblies, so that the conveyance of bag holding assemblies in an empty state (i.e., a state with no bag) can be prevented.
Furthermore, in the above-described calculation example, the switching of the speeds of the respective driving motors was assumed to be instantaneous. In an actual apparatus, however, the switching of the speeds of the driving motors cannot be accomplished instantaneously, and acceleration and deceleration are necessary only at the time of switching. Accordingly, calculations must be performed with this point taken into account.
To describe the structure of the continuous bag-supplying apparatus 1 in somewhat greater detail, the bag holding assembly conveying device 4 which is a part of the continuous bag-supplying apparatus 1 comprises, as shown in FIGS. 11 through 13, a reciprocating driving mechanism 9 and a rotational conveying mechanism 8. The reciprocating driving mechanism 9 is disposed on the surface of a bed 11, and the rotational conveying mechanism 8 is disposed on top of the reciprocating driving mechanism 9 and rotationally conveys a plurality of bag holding assemblies 3 along an annular track that has a pair of parallel sections.
The reciprocating driving mechanism 9 comprises: sliding members 14 through 16 which are disposed on the undersurfaces of supporting stands 12 and 13; rails 17 through 19 which are fastened to surface of the bed 11 and over which the sliding members 14 through 16 slide; bearings 21 and 22 which are fastened to the surface of the bed 11; a screw rod 23 which is rotatably supported by the bearings 21 and 22; a variable-speed driving motor (servo motor) M2 which rotationally drives the screw rod 23; and a nut member 24 which is fastened to the undersurface of a frame 12 and is screw-engaged with the screw rod 23. The rotational conveying mechanism 8 is caused to perform a reciprocating motion to the left and right by driving the driving motor M2 in the forward and reverse directions.
The rotational conveying mechanism 8 is equipped with: left and right supporting shafts 26 and 27 which are rotatably supported on a frame 25; a pair of pulleys 28 and 29 which are fastened to the supporting shafts 26 and 27 and are driven by a driving motor (servo motor) M1 with a variable rotational speed so that the pulleys 28 and 29 rotate in the horizontal plane; and a conveyor belt (timing belt) 31 which is installed between the pulleys 28 and 29. Bag holding assemblies 3 that each comprises a pair of holding members (left and right holding members) 3a and 3b are attached to the outer circumferential surface of the conveyor belt 31 at equal intervals (pitch=p). Bags W are inserted and held in the longitudinal spaces or grooves demarcated by the holding members 3a and 3b and the conveyor belt 31.
In addition, opening-and-closing bag guides 32 and 33 which guide the movement of the bags W that are supplied to the bag holding assemblies 3 are disposed along the track of the bag holding assemblies 3 in positions above and below the bag holding assemblies 3 on the bag entry side A.
The opening-and-closing bag guides 32 and 33 are caused to open and close simultaneously (as indicated by the solid and two-dotted (imaginary) lines in FIG. 13) by the operation of air cylinder 34 via opening-and-closing mechanisms 35 and 36. When the opening-and-closing bag guides 32 and 33 are closed, the upper-side opening-and-closing bag guide 32 is positioned in front of the bags W, and the lower-side opening-and-closing bag guide 33 is positioned in front of the bags W and at the same time supports the lower ends of the bags W.
The timing of the opening and closing of the opening-and-closing bag guides 32 and 33 is set so that the opening-and-closing bag guides 32 and 33 are opened immediately prior to the stopping of the bag holding assemblies 3 so as to supply bags W to the bag holding assemblies 3; then, the opening-and-closing bag guides 32 and 33 are closed immediately after the bags W have been supplied, so that the bags W supplied to the longitudinal spaces or grooves of the bag holding assemblies 3 are prevented from dropping through or flying out in the forward direction and so that the movement of the bags W is guided.
The lengths of the opening-and-closing bag guides 32 and 33 are set so that the lengths are more or less equal to the width occupied by the plurality of bag holding assemblies 3 to which bags W are supplied.
Fixed bag guides 37 and 38 are disposed above and below in the area extending from the ends of the opening-and-closing bag guides 32 and 33, around the pulley 28 and as far as the vicinity of the rotary type transfer device 6. The fixed bag guides similarly prevent the bags W from falling through or flying out.
As seen from FIG. 13, in the intermittent bag-supplying device 5, which is a part of the continuous bag-supplying apparatus 1, n conveyor magazine type bag-supplying devices similar to that described in, for instance, Japanese Patent Application Laid-Open (Kokai) No. H8-337217 are lined up side by side.
More specifically, each of the bag-supplying devices is equipped with: a belt conveyor 39 which continuously conveys a plurality of bags that are placed in a state in which the bags are partially overlapped with the mouths of the bags facing forward and downward; guide plates 41 which are disposed on the left and right and guide both side edges of the bags; a fast-feeding belt 42 which rotates at a higher speed than the belt conveyor 39, separates the leading bag conveyed by the belt conveyor 39 from the following bags, and fast-feeds the leading bag forward; a vacuum-chucking extraction arm 44 which vacuum-chucks (by means of a suction plate attached to the tip end of the arm) the bags W that have stopped as a result of contacting a stopper 43 located in front and lifts the bags W a specified distance; and a vacuum-chucking swinging arm 45 which vacuum-chucks the bags W by means of a suction plate attached to the tip end of the arm 45 and pivots upward so that the bags W are brought precisely into the longitudinal spaces or grooves of the bag holding assemblies 3.
Furthermore, a rotary type transfer device 6 which has a plurality of transfer means 47 installed on the outer circumference of a rotor 46 at equal intervals that are the same as the attachment spacing (pitch=p) of the bag holding assemblies 3 is disposed beyond the point where the fixed bag guides 37 and 38 end on the bag exit side B. The rotor 46 is caused to rotate continuously by a driving motor (servo motor) not shown, and vacuum passages 48 formed in the rotor 46 open in the side surfaces of the transfer means 47. From the position where the vacuum passages 48 each face the front surface of the corresponding bag holding assembly 3 to a position where the vacuum passages 48 have rotated approximately 180xc2x0 C. from the above-described position facing the bag holding assembly 3, the vacuum passages 48 are connected to a vacuum pump (not shown).
On the bag exit side B, the transfer means 47 rotate in the horizontal plane at the same speed and timing as the continuously rotating bag holding assemblies 3. The transfer means 47 continuously chuck and receive bags W from the bag holding assemblies 3, and then transfer the bags W to the rotor 7 of the next process after completing half of a revolution.
Furthermore, extraction guides 49 are installed above and below beyond the fixed bag guides 37 and 38. The extraction guides 49 contact the rear sides of the bags W and guide the bags W along the rotational track of the transfer means 47 and assist the chucking.
Generally, packaging bag shapes have various width dimensions and length dimensions according to the type of product that is packaged. Accordingly, in continuous filling and packaging systems, it is desirable that the system have a structure that can handle various types of bags that have different dimensions. However, the continuous bag-supplying apparatus (and especially the container holding assembly conveying device) can only supply bags that have roughly the same dimensions in terms of both width and length.
Accordingly, the object of the present invention is to provide a continuous container-supplying apparatus that is capable of handling containers of various dimensions and shapes.
The above object is accomplished by a unique structure for a continuous container-supplying apparatus that comprises a container holding assembly conveying device and a container-supplying device, in which
the container holding assembly conveying device comprises a plurality of container holding assemblies that are disposed at equal intervals so as to be moved in one direction along an annular track which has a pair of parallel sections, the container holding assemblies being moved, on a first side of the parallel sections, intermittently in an action in which a distance of the intermittent movement is an integral multiple of an attachment spacing of the container holding assemblies, and the container holding assemblies being moved, on a second side of the parallel sections, continuously at a constant speed;
the container-supplying device simultaneously supplies a plurality of containers respectively to each of the plurality of container holding assemblies on the first side of the parallel sections; and
the continuous container-supplying apparatus supplies, by way of the container-supplying device, the containers in a plurality of rows to the container holding assemblies that are stopped on the first side of the parallel sections, the continuous container-supplying apparatus successively removing the containers from continuously moving container holding assemblies on the second side of the parallel sections; and in which
each of the container holding assemblies is: comprised of a right-side holding member and a left-side holding member that hold each of the containers between the right-side holding member and left-side holding member; provided at equal intervals on conveying bodies that run along the annular track; and adjustable in regards to the spacing between the right-side and left-side holding members thereof.
With the above structure, containers (e.g., packaging bags) that have various width dimensions can be handled.
In the above, the xe2x80x9cconveying bodiesxe2x80x9d refers to a long body such as a belt, chain and the like that runs along the annular track.
More specifically, the conveying bodies are installed in a vertical relationship; the left-side holding member and right-side holding member are respectively provided on either one of the conveying bodies; and a spacing adjustment means is provided so as to adjust a relative positional relationship, in regards to the running direction of the conveying bodies, between one of the conveying bodies on which the left-side holding member is provided and another one of the conveying bodies on which the right-side holding member is provided. More specifically, each of the container holding assemblies is comprised of a pair of the right-side and left-side holding members; two conveying bodies are disposed one on the other; and the left-side and right-side holding members are respectively provided on either one of the two conveying bodies. As a result, the left-side and right-side holding members of the container holding assemblies can be simultaneously adjusted in terms of the space in between at one time.
In the above-described continuous container-supplying apparatus, when the container holding assemblies are provided on the outside surfaces of the conveying bodies and hold container, it is desirable that the right-side and left-side holding members have vertical guide portions that hold left and right edges of the containers and back surface portions that are formed so as to face inward along the conveying bodies and extend from the guide portions. The spacing between the left and right guide portions is set so as to be roughly the same as or slightly greater than the width of the containers, and the spacing of the back surface portions is set so as to be slightly smaller than the width of the containers. The containers are thus held in the space that are defined by the guide portions and back surface portions and are open outwardly.
The above-described object is further accomplished by another unique structure for a continuous container-supplying apparatus that comprises a container holding assembly conveying device and a container-supplying device, in which
the container holding assembly conveying device comprises a plurality of container holding assemblies that are disposed at equal intervals so as to be moved in one direction along an annular track which has a pair of parallel sections, the container holding assemblies being moved, on a first side of the parallel sections, intermittently in an action in which a distance of the intermittent movement is an integral multiple of an attachment spacing of the container holding assemblies, and the container holding assemblies being moved, on a second side of the parallel sections, continuously at a constant speed;
the container-supplying device simultaneously supplies a plurality of containers respectively to each of the plurality of container holding assemblies on the first side of the parallel sections; and
the continuous container-supplying apparatus supplies, by way of the container-supplying device, the containers in a plurality of rows to the container holding assemblies that are stopped on the first side of the parallel sections, the continuous container-supplying apparatus successively removing the containers from continuously moving container holding assemblies on the second side of the parallel sections; and in which
each of the container holding assemblies is comprised of a right-side holding member and a left-side holding member that hold each of the containers between the right-side holding member and left-side holding member; and
a receiving stand that supports a bottom portion of each of the containers is further provided along the annular track and beneath the container holding assemblies, the receiving stand being adjustable in regards to a height thereof
With this structure, containers (e.g., packaging bags) of various length dimensions can be handled. The height adjustable receiving stand can be operated together with the right-side and left-side holding members that form the container holding assembly and are adjustable in regards to the spacing thereof.
Furthermore, the above-described container holding assembly conveying device is equipped with, for instance, a rotational conveying mechanism and a reciprocating driving mechanism. The rotational conveying mechanism rotationally conveys the plurality of container holding assemblies, that are disposed at equal intervals, in one direction along the annular track that has the pair or parallel sections, and the reciprocating driving mechanism causes the rotational conveying mechanism as a whole to perform a reciprocating motion over a specified distance along the parallel sections. These rotational conveying mechanism and the reciprocating driving mechanism are equipped with respectively independent driving sources. In this case, the container holding assemblies run at a movement speed produced by a synthesis of the rotational conveying and reciprocating motion.
Furthermore, a rotary type transfer device, which has a plurality of transfer means disposed at equal intervals, may be installed on the second side of the parallel sections as a part of the continuous container-supplying apparatus. The rotary type transfer device continuously receives containers from the container holding assemblies by continuously rotating transfer means and then continuously supplies the containers to the rotor of the device of the next process. In other words, the container holding assembly conveying device continuously supplies containers via the rotary type transfer device. Needless to say, the installation spacing and movement speed of the rotary type transfer means are set so as to agree with those of the container holding assemblies.